From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3F316C10F00 for ; Thu, 21 Mar 2019 07:58:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 10B0E218E2 for ; Thu, 21 Mar 2019 07:58:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="WLZq8L8B" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728087AbfCUH6P (ORCPT ); Thu, 21 Mar 2019 03:58:15 -0400 Received: from mail-pg1-f196.google.com ([209.85.215.196]:45826 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728069AbfCUH6N (ORCPT ); Thu, 21 Mar 2019 03:58:13 -0400 Received: by mail-pg1-f196.google.com with SMTP id y3so3657536pgk.12 for ; Thu, 21 Mar 2019 00:58:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=dfCfOEPJnXrjKZNyGXOlfp7qK4c6wG8AdxQp4q9noKA=; b=WLZq8L8BdoGlwZbLh0l+o0poOxozL0k/PA7aeuqn9qQhY82y8pbLx4Z60FMPfvOEfs r6r67PuYKJUqQlU108D7JJ60uN8fx3vEHplSldfdRKNgKYpsLP6569s2h0GNeSGmEIMZ tJME8aFhKIZJNLxKsV5OjLIFtHQ34Oy+a6/xdmQpG0yLzKM8trMx85XPUABTGvJUWSCQ sdpFEnYjZbE0dZhbPd/+f5WzX+0dBYYaU3yzCtb7R+ml24EFavmNQiB/Pf2XDPUXXOnW /0k3bOgYqA8R/zMSm8msxA7fYyCFeqE4Ox1pDbTAVVdKrQzMm7dvOM5FU2CY2iSO5Ea6 XK9g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=dfCfOEPJnXrjKZNyGXOlfp7qK4c6wG8AdxQp4q9noKA=; b=RbE/DOVId8pMKCU/k+HoUwl3+/C3WHNH2D7kQnE3Lt6iKzrCMp4Q4qE16zMZV8AzFN vqAXqjqnipd+Suxcvc2jDCtmcUZzEX2c6e2voyUrJG28slWh8lVcVcgh445jyPVoP2Cb QReZkwZYBZhBA7zR2tKfJD2hskKjc8DohURSJyZdztUws4V+Nq+9SODbpjM+bzMYZ48b 2P3YTziniDu8KuVod2y50cro6MMiVP/OmK3I7sTosk87osPE3wqNcXbgSrxiwsNZ+mLH izUE1D5UrKB9K7xGJq4UR4fLFPYDp3Lrjdq9g9bdKSggl48j6JNUtSosCppwpt+nl2hF fhfg== X-Gm-Message-State: APjAAAVfJMbW7ZKANGdWieCpHnPIhS1qE2KBzx9A18EZ9lSgkGVEX/Bo H50kmyTGKeo9D684QYOixvM= X-Google-Smtp-Source: APXvYqyHQ3r164fXgiwh0PcPJ5fSOkLUNTtZLqKLE1sUpJvAVA5CunZ4kRUtNiyTbkbJ4oArWRjIng== X-Received: by 2002:a62:4649:: with SMTP id t70mr2125697pfa.100.1553155092538; Thu, 21 Mar 2019 00:58:12 -0700 (PDT) Received: from localhost.localdomain ([203.100.54.194]) by smtp.gmail.com with ESMTPSA id e184sm6467148pfc.143.2019.03.21.00.58.09 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 21 Mar 2019 00:58:12 -0700 (PDT) From: Yuyang Du To: peterz@infradead.org, will.deacon@arm.com, mingo@kernel.org Cc: bvanassche@acm.org, ming.lei@redhat.com, linux-kernel@vger.kernel.org, joe@perches.com, Yuyang Du Subject: [PATCH v3 13/18] locking/lockdep: Change type of the element field in circular_queue Date: Thu, 21 Mar 2019 15:57:20 +0800 Message-Id: <20190321075725.14054-14-duyuyang@gmail.com> X-Mailer: git-send-email 2.17.2 (Apple Git-113) In-Reply-To: <20190321075725.14054-1-duyuyang@gmail.com> References: <20190321075725.14054-1-duyuyang@gmail.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The element field is an array in struct circular_queue to keep track of locks in the search. Making it the same type as the locks avoids type cast. Also fix a typo and elaborate the comment above struct circular_queue. No functional change. Signed-off-by: Yuyang Du Reviewed-by: Bart Van Assche --- kernel/locking/lockdep.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index f46695a..8167d69 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1272,13 +1272,16 @@ static int add_lock_to_list(struct lock_class *this, #define CQ_MASK (MAX_CIRCULAR_QUEUE_SIZE-1) /* - * The circular_queue and helpers is used to implement the - * breadth-first search(BFS)algorithem, by which we can build - * the shortest path from the next lock to be acquired to the - * previous held lock if there is a circular between them. + * The circular_queue and helpers are used to implement the graph + * breadth-first search (BFS) algorithm, by which we can determine whether + * there is a path from the next lock to be acquired to a previous held + * lock, which indicates that adding the -> lock dependency + * produces a circle in the lock dependency graph. Breadth-first search + * instead of depth-first search is used for finding the shortest circular + * path. */ struct circular_queue { - unsigned long element[MAX_CIRCULAR_QUEUE_SIZE]; + struct lock_list *element[MAX_CIRCULAR_QUEUE_SIZE]; unsigned int front, rear; }; @@ -1304,7 +1307,7 @@ static inline int __cq_full(struct circular_queue *cq) return ((cq->rear + 1) & CQ_MASK) == cq->front; } -static inline int __cq_enqueue(struct circular_queue *cq, unsigned long elem) +static inline int __cq_enqueue(struct circular_queue *cq, struct lock_list *elem) { if (__cq_full(cq)) return -1; @@ -1314,7 +1317,7 @@ static inline int __cq_enqueue(struct circular_queue *cq, unsigned long elem) return 0; } -static inline int __cq_dequeue(struct circular_queue *cq, unsigned long *elem) +static inline int __cq_dequeue(struct circular_queue *cq, struct lock_list **elem) { if (__cq_empty(cq)) return -1; @@ -1392,12 +1395,12 @@ static int __bfs(struct lock_list *source_entry, goto exit; __cq_init(cq); - __cq_enqueue(cq, (unsigned long)source_entry); + __cq_enqueue(cq, source_entry); while (!__cq_empty(cq)) { struct lock_list *lock; - __cq_dequeue(cq, (unsigned long *)&lock); + __cq_dequeue(cq, &lock); if (!lock->class) { ret = -2; @@ -1421,7 +1424,7 @@ static int __bfs(struct lock_list *source_entry, goto exit; } - if (__cq_enqueue(cq, (unsigned long)entry)) { + if (__cq_enqueue(cq, entry)) { ret = -1; goto exit; } -- 1.8.3.1